1. Field of the Invention
This invention relates to a novel buckle assembly. In particular, the invention relates to a plug and socket type buckle assembly for use on various articles such as luggage and clothing.
2. The Prior Art
Plug and socket type buckles are useful for connecting two ends of a strap together on various articles such as luggage and outerwear. These types of buckles have a plug member connected to one end of a strap and a socket member connected to an end of a second strap. The straps are connected by locking the plug into the socket. Typically these plug and socket type buckles have a way of easily releasing the plug from the socket, such as by a center push button on the socket.
One example of this type of device is shown in U.S. Pat. No. 4,866,819 to Kasai. In this device, the plug side of the buckle has a thin plate portion with two resilient locking legs. A locking lug is disposed on the underside of each locking leg. When the plug is inserted into the socket, the lugs on each locking leg engage a retaining surface in the socket member and lock the plug and socket together. A release button is located on the socket, which pushes the lugs free of the retaining surface to release the plug from the socket. Various other types of plug and socket type buckles are disclosed in U.S. Pat. Nos. 4,802,262, 4,999,886 and 4,864,700 all to Kasai.
These buckles enable the user to easily lock and unlock two straps together. However, they all suffer from the drawback of insufficient strength under high degrees of tension. Since the lugs are located on only one side of the locking legs, excessive angular pressure on the buckle from a strap being pulled can cause the buckle to inadvertently release.
Another drawback of the prior art devices is that they only lock when the pieces are in one particular orientation. Turning either the plug or the socket 180 degrees will prevent locking of the device. This feature can be inconvenient, especially if a user is rushed or is attempting to lock the buckle in unlit conditions.